1, ketchup and lemon are made for seasoning.

2. Homemade tomato sauce with lemon is used for seasoning, and adding lemon can increase the sour taste of tomato sauce. Secondly, adding lemon helps to prolong the shelf life of tomato sauce, because lemon is rich in vitamin C, which can delay the deterioration of tomato sauce. It should be noted that vitamin C will decompose when heated, so lemon in tomato sauce can be added at the end.